It isn't identical. With a fixed ROM, every user is denied an opportunity to upgrade rather than just those without an anointed OS. It's about equal access.
Nevertheless, the first thing the driver for wifi in my laptop does is load up a big firmware file from disk, caused to be shoved into IC RAM, and then proceed to connect to the network. That this process could somehow become more free by embedding a frozen firmware image blows my mind.
And it's not like I haven't seen what the other side looks like. The Broadcom "full MAC" chipsets are also supported, with their remotely exploitable firmware. But those are also "fully" free. Hurray.